This research is interdisciplinary in nature, combining professional expertise from the biomedical and public health disciplines of the Columbia University Faculty of Medicine with the behavioral, social sciences, and educating disciplines of the Center for Health Promotion at Teachers College, Columbia University. The long-term objective of this collaboration is to build a team of investigators to identify the determinants of diet and physical activity behaviors in children that place them at increased risk for coronary heart disease later in life, and to develop guidelines and recommendations that will be useful in planning and implementing health promotion interventions designed to reduce population-wide risk factors. Specific aims are to: (I) Develop and evaluate a screening instrument to identify families in which children are at risk to developing health-compromising dietary and physical activitiy behaviors; (II) Demonstrate that children's dietary behaviors are influenced by personal, familial, and social factors; (III) Demonstrate that children's physical activity behaviors are influenced by personal, familial, and social factors; (IV) Identify clusters of variables that can be used to formulate indices accounting for the variance in children's dietary and physical activity behaviors over time; (V) Determine the extent to which these behaviors are stable over time; (VI) Estimate the reliability and validity of data collected on these behaviors; (VII) Estimate the reliability of data utilized for testing hypotheses; (VIII) Explore the role of socicultural and temporal factors in dietary and physical activity behaviors; (IX) Investigate why changes in diet and physical activity occur; and (X) Develop guidelines for designing and implementing health promotion intervention programs. The study design calls for repeated measures of the dietary and physical activity behaviors of 200 low-income Hispanic and Black children ages 3-4 years and their families over a three-year period. Data will be collected using biophysical measures, personal interviews, focus groups, direct and videotaped observations, and record review. Descriptive, univariate, and multivariate statistical methods will be used to analyze and identify groups at high risk for health-compromising behaviors, and to determine the extent to which these variables are predictive of behavior and risk at different points in time.